About 34 births per 1,000 women ages 15-19 occurred in 2010 in the U.S., compared to 22.5 in Minnesota. The seven states with lower birth rates are all located in the northeast, with New Hampshire leading the way at 15.7 births per 1,000 teen women. Wisconsin had the 10th-lowest teen birth rate among states.

But Minnesota health officials who follow the numbers say it's not all good news.

"When you look at our state ranking, we rank very well. But that masks some of the huge disparities we have within the state," said Mary Jo Chippendale, the infant, adolescent and women's health supervisor at the Minnesota Department of Health.

The state continues to have wider racial disparities when it comes to teen birth rates than the nation, Chippendale said.

The birth rate among American Indian and Hispanic teens in Minnesota is more than three times higher than the rate for white teens. The rate is also higher for African Americans and Asian/Pacific Islanders than for whites.

Health officials attribute the overall decline in birth rates to effective use of contraception and educational programs aimed at preventing teen pregnancy. Sexual activity among Minnesota teens has increased slightly in the last few years.

Chippendale said there can be fluctuations in the numbers from year to year, but she said she expects the overall downward trend to continue.

"I would hope that with the programs we have we would continue to see that kind of a trend, and at the very least would be able to maintain a steady pace," she said. "You need to try to sort through what's been successful."

The decline is likely not tied to decreased sexual activity or an increase in teens having abortions. Sexual activity among Minnesota teens has increased slightly in the last few years, and the number of Minnesota teens having abortions has declined by 31 percent in the four-year period that ended in 2010, according to student survey data and the Minnesota Department of Health's annual report on abortion procedures.

Judith Kahn, executive director of Teenwise Minnesota, said her organization and others are celebrating the good news but still have work to do to prevent teen pregnancies.

"We also need to remain vigilant, so as the next generations of young people come along, they too have access to really high quality and accurate medical information," she said.

Kahn said it's important to keep a state law that allows teens to receive health care without a parent's consent. She also noted that the amount of information teens receive about sexual health varies from school district to school district.

Health officials care about the teen births because they're associated with unfavorable outcomes for the teens and their children — including lower graduation rates, high rates of poverty, premature birth and low birth weight.